Safety discharge valve



Oct. 13, 1936. E. KAGI SAFETY DISCHARGE VALVE Filed Jul 'so, 1934 2 Sheets-Sheet 1 Fig. 3

Fig.1

\nvemor 2 Oct. 13, 1936.

E. KA GI SAFETY DISCHARGE VALVE Filed July 50, 1934 2 Sheets-Sheet 2 f/ llllfllll/llll/lllz lllll/llflllfllll Patented Oct. 13, 1936 UNITED STATES PATENT OFFICE Application July 30, 1934, Serial No. 737,642 In Switzerland July 31, 1933 Claims.

I have filed applications in Switzerland on the 31st July, 1.933 and 18th August, 1933.

The present invention relates to safety discharge valves for hot water boilers.

The safety discharge valves provided with weights or loaded pistons have in recent times been replaced by valves provided with diaphragms. Such valves become inoperative after a very short time unless they are interposed in a 10 feed pipe, as otherwise the diaphragms are damaged or destroyed by the action of hot water and steam. Under normal working conditions, valves provided with diaphragms and interposed in a feed pipe or conduit work satisfactorily and answer all requirements. Should it, however, occur that the temperature regulatorstops functioning from any cause so that the water in the boiler is heated up to steam generating temperature, the result is that the contents of the boiler are forced by the occurring high pressure out of the boiler and through the safety discharge valve, so that the boiler contains only steam.

A further result of this failure of the temperature regulator, may be overheating of the heater, particularly in cases of electrically heated boilers, until glowing temperature is reached, and finally the insulation may be set on fire endangering the whole building in which the heaters are used.

The object of the present invention is to provide a safety discharge valve or so-called overload valve, which is adapted to be connected to two conduits conveying difierent media, for instance, hot water and cold water pipes of a hot water boiler, and is so constructed that the sensitive members of the valve are at least temporarily exposed to the action of a cooling medium, in such a manner that both the sensitive valve members and the discharged hot water are cooled upon the valve coming into operation.

Several constructions embodying the features of the invention are shown by way of example in the accompanying drawings, in which: I

Fig. 1 is a sectional elevation of the first construction,

'Fig. 2 is a diagram showing the arrangement of the valve in a boiler circuit,

Fig. 3 is a sectional elevation of the second construction,

Fig. 4 is a corresponding diagram showing the arrangement of the valve in the boiler circuit,

Fig. 5 is a section elevation of a third construction,

Fig. 6 a diagram showing the arrangement of the valve in a boiler circuit, and

Fig. 7 is a sectional elevation of a fourth construction,

Fig. 8 being a diagram of the arrangement or" the valve in a boiler circuit.

Referring first to Fig. 1, l indicates a main valve casing provided with a branch connection 2 for the admission of hot water, a branch connection 3 for the admission of cold water and a branch connection 4 for the discharge of water. 5 indicates a valve mounted in the casing l by means of a diaphragm 6 and loaded by a helical spring 8, the compression of which can be regulated by means of a screw 1. From the branch 2 extends downwardly and coaxially with the valve 5 a hot water pipe 9, the lower end of which acts 1 as a valve seat. Coaxially with the pipe 9 extends a pipe ID the lower end of which also acts as a valve seat co-operating with valve 5. The valve 5 carries between the pipe it and the lower end of pipe 9 a tubular member I I which projects into the annular space between the pipes 9 and It.

The operation of this valve is as follows:-

If the pressure in the boiler exceeds a predetermined value, for which the valve loading spring 8 has been set, the valve is depressed and moved from its double seat 9, l3 by the steam pressure against the action of the spring 8, the flexible diaphragm permitting of this movement. Hot water then passes from the pipe 9 into the annular space 13 between the pipes 9 and I0 and flows into and through the exit branch 4. At the same time, fresh water passes from the branch 3 into the annular space 13 and into the exit branch 4. As soon as the boiler pressure drops to the permitted value, the operation is reversed, and the valve closes under the pressure of the spring i 9.

It may be pointed out that the valve seats con trolling the hot water and the cold water flowing through the valve can obviously be arranged in various ways without departing from the scope of the invention, for instance, they could be arranged in series in the axial direction. The illustrated arrangement, however, has the advantage of great simplicity.

The diaphragm 6 may be of any suitable material, for instance, rubber, metal, metal alloy, or rust-free steel.

Fig. 6 shows diagrammatically the arrangement of a counter-current safety discharge valve according to Fig. 1 in a boiler circuit. B indicates the boiler, V the improved valve according to the invention, K the cold water conduit, H the hot water conduit and S a valve. The improved safety discharge valve according to the invenposed to the cooling action of the water.

tion is suitable also for other installations, and other media, for instance, gases.

A particularly advantageous construction is obtained by designing the valve in such a manner that it may be interposed as a through passage valve in the cold water pipe of a boiler installation, so that thevalve and its parts are exposed even at normal pressure conditions to the cooling action of the cold water.

Figs. 3 and 4 show by way of example such a construction in which the cold water passes continuously around the valve.

In this construction the valve I again provided with a branch connection 2 for the hot water, 3a for the cold water admission, 31) for the cold water discharge, and 4 for the safety discharge. The safety discharge branch connection 4, is, in this case, displaced through with regard to the branches 3a and 3b. Otherwise this construction is substantially identical with that shown in Fig. 1. 5 again indicates a valve mounted in the casing by means of a diaphragm 6, 1 is a pressure adjusting screw, 8 a compression spring loading the valve, 9 is the hot water pipe, [0 a valve socket the lower end of which constitutes a seat, H a tubular member connected with the valve and extending into the annular space l2, l3 between the socket l0 and the pipe 9.

In Fig. 4.13 is the boiler, K the cold water supply pipe provided with the improved valve V and an ordinary stop valve S, H is the hot water pipe.

The operation of the valve is as follows:

As cold water continuously enters the valve through branch 3a and is discharged through branch 3b, the cold water flows continuously around thesensitive parts of the valve and consequently these valve parts are continuously ex- If the pressure in the boiler exceeds the permitted value determined by the compression of the spring 8, the valve 5 is opened by the overpressure of the hot water against the action of the spring 8, the flexible diaphragm 6 permitting of this movement of the valve away from the double seat 9, 10. Consequently hot water passes through the annular space l2 to the discharge branch 4 and simultaneously fresh water passes from the cold water supply into the annular space [3 and the discharge branch 4. As soon as the boiler pressure drops to the permissible value, the valve closes.

The construction shown in Figs. 5 and 6 permits of greater facility in the disposition of the valve and the mounting thereof.

In this construction the valve casing I is provided with an annular projecting portion l4 upon which is turnably mounted a casing [5 containing a discharge branch connection 4. The discharge branch 4 can therefore be adjusted angularly about the axis of the valve through an angle of 360. After suitable adjustment the casing l5 can be fixed in position relatively to the casing I by means of a nut l6.

Fig. 6 explains the arrangement of the valve according to Fig. 5 in a boiler circuit.

Fig. '7 shows a construction which is substantially similar to those shown in Figs. 1, 3, and 5 and Fig. 8 shows the arrangement of the valve according to Fig. '7 in a boiler circuit.

In this construction, hot water coming from the boiler enters the valve through the branch connection 4 and is discharged from the valve (Fig. 3) is through pipe 9 and branch connection 2 as indicated by arrows.

I claim:

1. In an automatic safety discharge valve for hot water boilers, the combination of: a valve casing; a diaphragm-valve and a valve seat in said casing; a cold water conduit in said casing for passing cold water through said casing; another conduit in said casing for passing a medium of a high temperature from the hot water boiler through said casing; said medium auto- .matically operating said diaphragm valve, and both said conduits being controlled by said valve;

ing and adapted to open and close simultaneously the passages of the cold water and the hot water through the casing to the common discharge branch; said diaphragm-valve being automatically operated by the pressure of the hot water and steam coming from the boiler and the cold Water passage within the valve casing being so constructed as to enclose and cool the diaphragm, the valve and the valve seat, substantially as described.

3. In an automatic safety discharge valve for hot water boilers, the combination of: a casing;

a cold water filled conduit for passing cold water through the casing; a high temperature medium conduit for passing hot water and steam from the boiler through the casing; diaphragm-valve means in said casing for controlling the said conduits, said valve means being spring-loaded; and being automatically operated by the pressure of the hot water and steam'coming from the boiler;

said coldwater conduit and said diaphragm-valve means being so constructed that the said diaphragm and valve are surrounded and cooled by the cold water, substantially as described.

4. In an automatic safety discharge valve for hot water boilers, the combination of: a valve casing; a cold water filled conduit for passing.

cold water through said casing; a conduit for passing hot water and steam from the boiler through said casing; and a single spring loaded diaphragm-valve adapted to be automaticallyoperated by the pressure of the hot water and steam coming from the boiler and to control simultaneously both said conduits, said diaphragmvalve being surrounded by the cold water, substantially as described.

5. In an automatic safety discharge valve for hot water boilers, the combination of: a valve casing; a cold Water filled conduit for passing cold water through said casing; a conduit for passing steam and hot Water from the boiler.

through said casing; a single spring loaded diaphragm-valve adapted to be operated by the pressure in said last named conduit and to control simultaneously said two conduits; two coaxial valve seats co-operating with said single diaphragm-valve, one of said valve seats being associated with the steam and hot water con-' duit and the other valve seat being associated with the cold water conduit; the cold watercond'uit being so constructed as to surround said diaphragm and valve and the corresponding valve seat and the portion of the hot water conduit leading to the valve so as to exert a cooling action upon them, substantially as described.

6. In an automatic safety discharge valve for hot water boilers, the combination of: a casing; a high temperature medium admission pipe leading from the boiler and communicating with a first valve seat; a discharge conduit in said casing; a cold water filled conduit in said casing; a tubular member in said casing in constant cornmunication with said discharge conduit and in communication with a valve seat controlling the passage of the cold water, said tubular member being coaxial with said high temperature medium admission conduit; and a single spring loaded diaphragm-valve operated by the pressure in said high temperature medium admission pipe and co-operating with said high temperature medium admission passage and said tubular member, said cold water conduit enclosing said tubular member and said valve, substantially as described.

7. In an automatic safety discharge valve for hot water boilers, the combination of: a casing; a high temperature medium admission pipe leading from the boiler and communicating with a first valve seat; a discharge conduit in said casing; a cold water filled admission conduit in said casing; a tubular member in said casing in constant communication with said discharge conduit and in communication with a valve seat controlling the passage of the cold water, said tubular member being coaxial With said high temperature medium admission conduit; and a single spring loaded diaphragm-valve operated by the pressure in said high temperature medium admission conduit and co-operating with said tubular member, said cold water admission conduit enclosing said tubular member and said valve, said valve carrying a tubular member projecting into the annular space between said high temperature medium passage and said tubular member, substantially as described.

8. In an automatic safety discharge valve for hot water boilers, the combination of: a casing; a high temperature medium admission pipe leading from the boiler and communicating with a first valve seat; a discharge conduit in said casing; a cold water filled admission conduit in said casing; a tubular member in said casing in constant communication with said discharge conduit and in communication with a valve seat controlling the passage of the cold water, said tubular member being coaxial with said high temperature medium admission pipe; and a single springloaded diaphragm-valve operated by the pres sure in said high temperature medium admission pipe and co-operating with said tubular member, said cold water admission conduit enclosing said tubular member and said valve and diaphragm, whereby the valve and valvev seat and diaphragm are continuously cooled, substantially as described.

9. In an automatic safety discharge valve for hot water boilers, the combination of: a casing; a high temperature medium admission pipe leading from the boiler and communicating with a first valve seat; a discharge conduit in said casing; a cold water filled admission conduit in said casing; a tubular member in said casing in constant communication with said discharge conduit and in communication with a valve seat controlling the passage of the cold water, said tubular member being coaxial with said high temperature medium admission pipe; and a single valve operated by the pressure in said high temperature medium admission pipe and co-operating with said tubular member, said cold water admission conduit enclosing said tubular member and said valve, said valve carrying a tubular member projecting into the annular space between said high temperature medium pipe and said tubular member, and said valve being spring-loaded and provided with a diaphragm, substantially as described.

10. In an automatic safety discharge valve for hot water boilers, the combination of: a casing; a high temperature medium admission pipe leading from the boiler into said casing, the end of said pipe forming a valve seat; a coaxial tubular member in said casing, the end of said member forming a second valve seat; a valve coaxial with said admission pipe and said tubular member and adapted to co-operate with the said valve seats; said common valve being provided with adjustable spring means and a diaphragm, said diaphragm separating said spring means from the interior of said valve casing, means for adjusting the compression of said spring means accessible from the outside; a cold water filled conduit surrounding said tubular member and said valve; a discharge conduit communicating with an annular space between saidhigh temperature medium admission pipe and said tubular member; and a second tubular member carried by said valve and arranged in the said annular space, substantially as described.

11. In an automatic safety discharge valve for hot water boilers, the combination of: a casing; a cold water conduit in said casing through which cold water passes continuously through the casing; a high temperature medium admission pipe leading from the boiler into said casing; a common discharge branch in said casing; a tubular 'member in said casing coaxial with the end of said high temperature medium admission pipe; an annular space between said tubular member and said high temperature medium admission pipe being constantly in communication with said common discharge branch; a common diaphragm-valve controlling simultaneously the inner opening of said high temperature admission pipe and said tubular member; said valve and said tubular member being in the line of flow of the low temperature medium, the low temperature medium conduit surrounding said tubular member and cooling same and the diaphragm and valve constantly, substantially as described.

12. In an automatic safety discharge valve for hot water boilers, the combination of z a casing; a cold water filled conduit in said casing through which cold water passes continuously through the casing; a high temperature medium admission pipe in said casing; a common discharge branch in said casing; a tubular member in said casing coaxial with the end of said high temperature medium admission pipe; the annular space between said tubular member and said high temperature medium admission pipe being constantly in communication with said common discharge branch; a common diaphragm-valve controlling simultaneously the inner opening of said high temperature admission pipe and said tubular member; said valve and said tubular member being in the line of flow of the cold water, the cold water conduit surrounding said tubular member and cooling same and the diaphragm 13. In an automatic safety discharge valve for hot water boilers, the combination of va casing;

a high temperature medium admission conduit leading from the boiler to the casing; a cold water conduit through which cold Water continuously passes through the valve casing; a

common safety discharge conduit through which the high temperature medium and the cold water can pass out of the casing; a double diaphragmvalve for simultaneously controlling the passage of the cold'water and the high temperature medium into said common discharge conduit; said :valve being operated by the pressure in said high temperature medium admission conduit and lying in the line of flow of the cold water, so that said valve and diaphragm are continuously cooled by the flow of the cold water, substantially as 'described.

14. In an automatic safety discharge valve for hot water boilers, the combination of: a valve casing; a high'temperature medium admission conduit leading from the boiler to said casing; a cold Water conduit through which cold water continuously passes through the valve casing; a common safety discharge conduit through which the high temperature medium and the cold water can pass out of the casing; a double diaphragmvalve for simultaneously controlling the passage of the low temperature medium and the high ternthe cold water, said valve being spring loaded,

substantially as described. I

15. In an automatic safety discharge valve for hot water boilers, the combination of: a valve casing; a high temperature medium admission conduit leading from the boiler to the casing; a cold water conduit through which cold water con& tinuously passes through the valve casing; a

common safety discharge conduit through which;

the high temperature medium and the cold water can pass out of the casing; a double diaphragmvalve for simultaneously controlling the passage of the cold water and the high temperature medium into said common discharge conduit; said valve and diaphragm being operated by the pressure in said high temperature medium admission conduit and lying in the line of flow of the cold Water .so that said valve and diaphragm are continuously cooled by the flow of the cold water,

said common discharge conduit being angularly adjustable with regard to said casing, substantially as described.

EMIL KAGI. 

